Asymmetric Total Synthesis of Rugulactone, an α-Pyrone from Cryptocarya rugulosa

Abstract

A total asymmetric synthesis of rugulactone, a naturally occuring α-pyrone isolated from Cryptocarya rugulosa, is reported. The synthesis involved a cross-metathesis coupling reaction to construct the internal E-olefin group, a Still-Gennari olefination to construct the Z-configured α,β-unsaturated ester group, and a one-pot deprotection and intramolecular lactonization reaction. The stereo­chemistry at C5 was controlled by the use of a chiral pool.

Key words

total synthesis - natural products - pyrones - metathesis - olefination

References

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27

The Z/E ratio was determined from the ^¹H and ^¹³C NMR spectra of compound 2 and confirmed by GC/MS.